Manipulating Graphs

Learning Resource Type

Classroom Resource

Subject Area

Mathematics

Grade(s)

7, 8

Overview

Watch how a graph is altered when key elements of the equation change. This lesson focuses on how to manipulate the equation of a line in slope intercept form to match the graphs provided deepening the understanding of both the slope and y intercept's role in the expression. This video was submitted through the Innovation Math Challenge, a contest open to professional and nonprofessional producers.

Mathematics (2019) Grade(s): 8

MA19.8.9

Interpret y = mx + b as defining a linear equation whose graph is a line with m as the slope and b as the y-intercept.

UP:MA19.8.9

Vocabulary

  • Slope
  • Rate of change
  • Initial Value
  • Y-intercept

Knowledge

Students know:
  • how to graph points on a coordinate plane.
  • Where to graph the initial value/y-intercept.
  • Understand how/why triangles are similar.
  • how to interpret y=mx equations.

Skills

Students are able to:
  • create a graph of linear equations in the form y = mx + b and recognize m as the slope and b as the y-intercept.
  • point out similar triangles formed between pairs of points and know that they have the same slope between any pairs of those points.
  • Show that lines may share the same slope but can have different y-intercepts.
  • Interpret a rate of change as the slope and the initial value as the y-intercept.

Understanding

Students understand that:
  • Slope is a graphic representation of the rate of change in linear relationships and the y-intercept is a graphic representation of an initial value in a linear relationship.
  • When given an equation in the form y = mx + b it generally symbolizes that there will be lines with varying y-intercepts. even when the slope is the same.
  • Use of the visual of right triangles created between points on a line to explain why the slope is a constant rate of change.
Mathematics (2019) Grade(s): 8

MA19.8.15

Compare properties of functions represented algebraically, graphically, numerically in tables, or by verbal descriptions.

UP:MA19.8.15

Vocabulary

  • Function
  • Linear
  • Non-linear
  • Slope

Knowledge

Students know:
  • how to find rates of change and initial values for function represented multiple ways.
  • how to graph functions when given an equation, table, or verbal description.

Skills

Students are able to:
  • identify the differences between functions represented in multiple contexts.
  • Tell the differences between linear and nonlinear functions.

Understanding

Students understand that:
  • Converting to different representations of functions can assist in their comparisons of linear functions qualitatively and quantitatively.

CR Resource Type

Audio/Video

Resource Provider

PBS

License Type

PD
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